Level.



No. 800,739. PATENTED OCT. 3, 1905. G. F. GROSSER.

LEVEL.

APPLICATION FILED DEC. 8, 1904.

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LEVEL.

Specification of Letters Patent.

Patented Oct. 3, 1905.

Application and DecembefS, 1904. Serial No. 235,913.

To all whom it may concern:

Be it known that 1, CHARLES F. GRossER, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Levels; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to levels, and has for its object to simplify and generally improve the same.

To the above ends the invention consists of the novel devices and combinations of devices hereinafter described, and defined in the claims.

In the accompanying drawings, which illustrate my invention, like characters indicate like parts throughout the several views.

Figure 1 is a view in side elevation with some parts broken away, showing a level designed in accordance with my invention. Fig. 2 is a section on the line m of Fig. 1. Fig. 3 is a view corresponding to Fig. 1, but illustrating a slightly-modified construction; and Fig. 1 is a section on the line 0* 0* of Fig. 3.

The numeral 1 indicates the body of the level, which is recessed at its central portion to aflord a seat 2 for the transparent bulb or bubble-chamber. In the construction illustrated in Figs. 1 to 4, inclusive, the bubblechamber is in the form of a hollow glass disk 3, which is round in circumference and double convex in cross-section. In the arrangement illustrated in Fig. 1 the sides of the bubblechamber 3, except at its peripheral portions, are covered by light metallic disks 1, which in turn are rigidly connected by radial arms 5 to the seat 2. The metallic disks 4: are graduated at their margins to indicate degrees. In the construction illustrated in Figs. 3 and 4 the metallic disks are dispensed with. The bubble-chamber 3 is seated directly in an annular frame 6, and the degree-graduations are marked directly on said "frame 6. The bubble-chambers 3 are so nearly filled with alcohol or some other suitable liquid that only a small air-bubble z is left therein for cooperation with the degree-graduations to indicate the angle at which the level is set.

What I claim, and desire to secure by Letters Patent of the United States, is as follows:

1. A level having a bubble-chamber, the periphery of which extends on the line of a complete circle, and which is double convex in transverse cross-section, substantially as described.

2. A level having interposed in its body portion, a transparent bubble-chamber 3, the periphery of which extends on the line of a complete circle and which in transverse crosssection is double convex, and a graduated annular scale surrounding said bubble-chamber and serving to hold the same in working position, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

CHARLES F. GROSSER.

Witnesses:

ROBERT C. MABEY, F. D. MERCHANT. 

